PR 5620

[pf3gnuchains/gcc-fork.git] / gcc / explow.c

diff --git a/gcc/explow.c b/gcc/explow.c
index f58873a..47cb867 100644 (file)
--- a/gcc/explow.c
+++ b/gcc/explow.c
@@ -577,34 +577,6 @@ validize_mem (rtx ref)
   return replace_equiv_address (ref, XEXP (ref, 0));
 }
 \f
-/* Given REF, either a MEM or a REG, and T, either the type of X or
-   the expression corresponding to REF, set RTX_UNCHANGING_P if
-   appropriate.  */
-
-void
-maybe_set_unchanging (rtx ref, tree t)
-{
-  /* We can set RTX_UNCHANGING_P from TREE_READONLY for decls whose
-     initialization is only executed once, or whose initializer always
-     has the same value.  Currently we simplify this to PARM_DECLs in the
-     first case, and decls with TREE_CONSTANT initializers in the second.
-
-     We cannot do this for non-static aggregates, because of the double
-     writes that can be generated by store_constructor, depending on the
-     contents of the initializer.  Yes, this does eliminate a good fraction
-     of the number of uses of RTX_UNCHANGING_P for a language like Ada.
-     It also eliminates a good quantity of bugs.  Let this be incentive to
-     eliminate RTX_UNCHANGING_P entirely in favor of a more reliable
-     solution, perhaps based on alias sets.  */
-
-  if ((TREE_READONLY (t) && DECL_P (t)
-       && (TREE_STATIC (t) || ! AGGREGATE_TYPE_P (TREE_TYPE (t)))
-       && (TREE_CODE (t) == PARM_DECL
-          || (DECL_INITIAL (t) && TREE_CONSTANT (DECL_INITIAL (t)))))
-      || TREE_CODE_CLASS (TREE_CODE (t)) == 'c')
-    RTX_UNCHANGING_P (ref) = 1;
-}
-\f
 /* Return a modified copy of X with its memory address copied
    into a temporary register to protect it from side effects.
    If X is not a MEM, it is returned unchanged (and not copied).